Background: During total hip or knee replacement there is blood loss, wich often requires allogenic blood transfusions. The risks associated with this practice are well documented in the literature, and numerous strategies have been employed to conserve blood following total joint arthroplasty. The aim of this study is to determine the efficacy of an autologous retransfusion drain system to reduce the postoperative allogenic blood transfusion rate and the lack of adverse effects when using it.

Method: We did a retrospective study of patients operated on hip and knee primary replacements during the first six months of 2008, which had a postoperative blood salvage and retransfusion (Bellovac ABT autotransfusion system-Astra Tech, Mölndal, Swedenn-), Group A, n=220 patients, and a control group, Group B, with patients operated on hip or knee replacements during the first six months of the year before, which had standard drainage system, n=177. In first group the drain was opened inmediatly after tourniquet release and the shed blood was returned to the patient after collecting up to 500 ml and no later than six hours after surgery. The pre-operative data for cardiopathy, angiopathy, preoperative anemia or anticoagulant treatment showed no significant differences for group A and B. We standardised the transfusion criteria in order to allow an accurate comparison between the two groups. Evaluation was done with the medical history and the pre-/postoperative hemoglobin values, postoperative blood loss and postoperative need of allogenic blood transfusion.

Results: The two groups showed no significant differences relating to the demographic data or the medical history. 17 patients (7.7 %) of the retransfusion group needed allogenic blood transfusion compared with 16 patients (9 %) of the control group B (p > 0.05). The hemoglobin values of group A versus the control group showed after the donation of the salvaged blood a significant difference (p = 0,0007) but only in the subgroup of total knee replacement. Only three adverse events were observed when using the recuperator, which were not a risk for patients life and were solved with the cessation of postoperative reinfusion.

Conclusions: The use of the autotransfusion system seems to reduce the postoperative allogenic blood transfusion rate but not statistical significant. Our study therefore confirms the safety of retransfusion drains